Method of eliminating static electricity from combustible roofs



June 24, 1930. N. cs. BuRGsTl-:R 1,767,275

METHOD OF ELIMINATING STATIG ELECTRICITY` FROM COMBUSTIBLE ROOFS Filed April 4, 1928 Patented June 24, 1930 PATENT oFFlcE NATHAN G. BURGSTER, F CHICAGO, ILLINOIS METHOD OF ELIMINATING STATIC ELECTRICITY FROM COMBUSTIBLE ROOFS Application led April 4, 1928. Serial No. 267,359.

This invention relates to a method of eliminating static electricity from the nonmetallic roofs or other surfaces of oil storage tanks and other structures.

An object of the invention is to provide a method of applying a continuous unbroken surface of metal over a non-metallic surface for eliminating the hazardous effect of static electricity.

Another object of the invention is to provide a method of eliminating fire hazards resulting from static electricity.

A further object of the invention is to provide a method of protecting oil storage tanks and other structures against static electricity.

The invention consists in covering a nonmetallic tank roof or a similar surface with a coating or film of metal, which is continuous and unbroken over the entire roof or top of the tank, for establishing an electrical conductor whereby static electricity will be conducted to the eaves of the roof whence it is led to the ground througheither the v metallic Walls of the lstructure or other conductors. f

I do not limit my invention to oil storage tanks, as it is applicable to any kind of building structure having a non-metal roof n and where it is desirable or necessary to eliminate static electricit as a tire hazard. The metal may be applic in various ways.

The metal may be melted and applied in such state by spraying it over the surk face to be protected, or the melted metal may be applied in other suitable manners. Metal foil may be used, in which event it is secured in place by its own adhesiveness or by suitable adhesive material. The metal may be zinc, aluminum, copper and the like.

Some roofs are made of sheets of nonmetallic material or of metallic material or of metallic coated material laid with overlapping joints. Roofs so constructed may 15 be protected by my method, in which event the metal is sprayed or otherwise scoured over the edges of such sheets, with all the metal so used to make a continuous unbroken grill-work over the surface.

59 The metallic film or coating applied by my process is secured in position by adhesion without the use of nails, clamps or the like, such security resulting from the method of application.

The metal may be reduced to fine particles and mixed with a suitable carrier whereby the same may be applied to the desired surface. Metal dust may be used if desired, and is applied by any suitable apparatus such as a spray. The drawings show generally two forms of application of the method of my invention.

On the drawings:

Figure l is a side elevation of a welllrnown type of oil storage tank.

Figure 2 is an enlarged fragmental vertical section through an upper corner of a tank, showing the metal covering of my invention in place.

Figure 3 is a top plan view of a tank,y the roof of which is constructed of sheets of material laid with overlapping joints, over which joints the metal conducting grill-work of my invention is applied.

Figure 4 is an enlarged vertical section through one of the joints of Figure 3, showinfr the manner of applying the metal conductor of my invention.

Asshown on the drawings:

The tank of Figure l comprises side 1 and top 2, constructed in the usual manner.

Figure 2 shows wooden uprights 3 carrying roof beams 4, on which roof beams is laid the wooden roof 5.

The outer shell of the tank is made up of steel plates for the sides 6 connected in the usual manner.

Composition material 7 is laid 'on top of the wooden roof 5 and over this composition is applied the metallic coating or layer 8 of my invention.

The construction shown in Figure 2 includes angle bars 9 suitably secured to the side Walls 6 of the tank, with bolts 10 passing through the bars 9 and fastening thereto the composition roof 7. A strip l1 of metal is laid over the margins of the composition roof, so that the bolts 10 will not tear the composition.

The metallic layer is applied over the en- Cil tire top 2 of the te.. a its ma ins over the bars ll and bolts l0, and eilte nis frown- Wardly a suicient distance to make electrical connection with the side Wall 6 of the tank.

Any static electricity will flow to th inargins or the layer S on the roof and be Conducted therefrom to the ground through the Wall G of the trink.

Should the ictnre haye side walls of non-metallic materiel, then snitabie connuetors suoli as cable may be eonneced to the coating 8 and carried to -e ground, where suitable connection is made.

rlhe roof shown in Figure 3 plurality of sheets 'l2 laid up with overlapping oints as shown best Figure el. There these s i 's i l, the metal coating (t my inie wel oyer tbe eomprlses a oyerlapp ng edg' hese sheets, i'ornnng :i ized covering, compr s s 123 and members the shorter transverse lil. rlhe metal coating d as shown in Figure L.l to cover @verle-.poing ends of the sheets li, and at the same ti ne to be securely fixed by adhesion to the roof".

The members 13 and li or s form of roof coating are secured t; to the metallic side will (3 or described with reference to Fi Vfn re 2 or may be connected by suitable cabigs not shown with the ground.

rlhe metal coating is secure(l in posiVon on the roof by adhesion, and being continuous and unbroken serves to conductany static electricity to the ground, thus eliminating fire hazards.

Most fires of wood top oil tanks are Caused by lightnin not so much from being direet1 hit thereby, but because the static electricity ignites the gases issuing from the tanks.

Any metallic fitting on the roof must be electri ally eonnec..ed to the metal Coating of my invention. This connection may Y be readily made when t e ine-tal is sprayed.

T he term oil st: i in the appended elan reservoir for storing n iannnable liquids.

The term composition material7 is used herein generally id inehnles any material used for covering 'he Wooden roof oi the storage tank.

lllhile I have described more or less precisely the details ot construction of my invention yet l do not Wish to be understood as limiting mysel'z thereto, as I an aware that chansies may be made in roportion 'li :e t: nk used herein and O ol parts and that materials may be substituted Without departing from the spirit and scope of my inyention.

l claim as my invention: The method of protecting roofs of oil tanks and the like against damage by lightnclrnles a ijf tank or Illinois.

NATHAN G. BURGSTER. 

